What the 4-digit code every commercial aircraft broadcasts actually tells air traffic control

Every commercial flight has a squawk code. Learn why there are only 4,096 codes, what 7500, 7600, and 7700 mean, and how ATC ...
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This 4-digit Airplane Code Helps Air Traffic Controllers Spot Emergencies in Seconds—Here’s What Travelers Need to Know

It has nothing to do with birds—though that’s closer to the truth than you may think.